Low Beam doesn't work,

I have a 1979 kz650sr and my low beam quit working. when I switch to high beam the running light goes out. The brake lights work in either position. I changed out the fuses. Any suggestions? Thanks

I'd say remove the headlight from the housing and check first the filiments as sometimes they break, touching inside the bulb. If it looks o.k., then check the wiring and then see if you have voltage at the three prong plug that goes to the bulb.

The ground circuit will be the Black with Yellow striped wire, the other colors will be high and low beam circuits.

Ok I removed the headlight. Could not tell if the filament was bad, but glass does have a very small brown blotch. I check the three prong plug going to the headlight and it has voltage at both spades. So replace the bulb right? Would a bad bulb make the tail light go out when the high beam is engaged or is this another problem? Thanks

I'd replace the tail light bulb too. I use #1157 bulbs for the front running/turn signal & brake lights, and #1156 for the rear turn signal bulbs.

Check your fuses for signs of overheating/melting the clips. Your bike probably uses the 1" long AGX glass tubed fuses, most auto parts stores and boating supply places can get them for you.

Probably 10,20,& maybe 30 amp fuses are available.

Lighting Color Codes On Most Kawasaki’s

HEADLIGHT
RED with BLACK stripe, High Beam.
RED with YELLOW stripe, Low Beam.
BLACK with YELLOW stripe, the ground circuit.

BRAKE/TAIL LIGHT
RED, Running or Tail Light.
BLUE,(sometimes with a Red stripe) Brake Light Circuit.
BLACK with YELLOW stripe, the ground circuit.

LEFT FRONT TURN SIGNAL
GREEN, Left front turn signal circuit.
BLUE, Left front running light circuit.
BLACK with YELLOW stripe, the ground circuit.

RIGHT FRONT TURN SIGNAL
GREY, Right front turn signal circuit.
BLUE, Right front running light circuit.
BLACK with YELLOW stripe, the ground circuit.

LEFT REAR TURN SIGNAL
GREEN, Left rear turn signal circuit.
BLACK with YELLOW stripe, the ground circuit.

RIGHT REAR TURN SIGNAL
GREY, Right rear turn signal circuit.
BLACK with YELLOW stripe, the ground circuit.Lighting

Thanks Mfolks. I really appreciate the detailed answer. You're an angel sent down by the Motorcycle gods. Anyways I replaced the headlight bulb and the brakelight worked as a result. It must be part of that circuit, but I didn't expect to see it in "series". I will keep the information you listed for future reference as I don't own a book for this cycle. Keep up the good work. Cheers